Re: [boost] [rangelib]Any interest or plans for boost review?

From: Larry Evans (cppljevans_at_[hidden])
Date: 2005-07-07 16:51:32

On 07/01/2005 06:47 AM, Thorsten Ottosen wrote:
> Larry Evans <cppljevans <at> cox-internet.com> writes:
[snip]
>>Are there any plans to request a formal review so that it's eventually
>>in boost?  I tried boost/range; however, as indicated by comments
>>in the above code, I had no luck.
> 
> Could you make an small example that shows what you want to do and why 
> boost.range cannot do it?
> 

What I want is:

<-------- cut here --------
#include <utility>
using namespace std;
template<class StlContainer>
struct const_iter_range
   : private std::pair
     < typename StlContainer::const_iterator
     , typename StlContainer::const_iterator
     >
{
         typedef
       typename StlContainer::const_iterator
     iter_type
     ;
         typedef
       typename StlContainer::const_reference
     const_reference
     ;
         typedef
       std::pair<iter_type,iter_type>
     super_type
     ;
     const_iter_range(StlContainer const& a_container)
       : super_type(a_container.begin(), a_container.end())
     {}

       const_reference
     operator*(void)const
     {
         return *(this->first);
     }

       void
     operator++(void)
     {
         ++(this->first);
     }

       bool
     empty(void)const
     {
         return (this->first) == (this->second);
     }

};
 >-------- cut here --------
However, when I tested boost/range by copying and then
simplifying libs/range/test/iterator_range.hpp, the
closest I got was:
<-------- cut here --------

     typedef string::iterator               iterator;
     typedef iterator_range<iterator>       irange;
     string       str  = "hello world";
     irange ir    = make_iterator_range( str );

     cout <<"print str:\n";
     cout <<str<<"\n";
     cout <<"iterating thru ri:\n";
     range_iterator<string>::type ri(begin(ir));
     for
       ( int i=0
       ;    i<2
         //&& !(ri.empty())
       ; ++i,++ri
       )
     {
         cout <<*ri << "\n";
     }
     return 0;
}-------- cut here --------
Why doesn't range_iterator<X> have an empty method?
It also seems a lot of trouble to first declare and
initialize the iterator_range used as argument to
range_iterator.  What's the reason for not doing
this directly from the iterator_range CTOR arg
which could just be an stl container?

I suspect I missed something, but it's not obvious,
at least to me :(